Systems and methods for collecting and distributing gray water

ABSTRACT

A gray water collection and distribution system includes a main drain line, one or more black water sources connected to the main drain line, one or more gray water sources connected to the main drain line and a collection valve located down stream from at least one of the one or more black water sources. The collection valve includes an inlet connected to the main drain line, and an outlet connectable which can be switched to either a black water drain line or a gray water drain line, depending upon which type of water flow is detected.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.60/319,387 filed Jul. 10, 2002, and entitled “Gray Water ReclamationSystem,” the contents of which are herein incorporated by reference inits entirety for all purposes.

BACKGROUND

The present invention relates to water reclamation systems, and inparticular to gray water reclamation systems.

As known in the art, “gray” water refers to water containing low levelsof contaminants and which is typically not potable, but can be recycledand used in particular applications, such as irrigation water, toiletwater, as well as some industrial applications. “Black” water isdistinguished from gray water in that black water contains a high amountof particulates and/or contaminants which requires heavy watertreatment. Fresh or “white” water is water which is most commonly usedby people for drinking and cooking.

While fresh water is absolutely essential for life, it has become adiminishing resource around the world. As populations in arid areascontinue to expand, drought conditions affect wide spread areas, andpollution from factories and plants contaminate water reserves, freshwater is becoming more difficult to obtain, and increasingly expensivewhen it is possible to do so. In certain areas around the globe, freshwater has been completely exhausted or contaminated, and this trend isexpected to become more pervasive in larger and more industrial areas.

Gray water reclamation has been a central point in proposed approachesto conserve fresh water resources. Many of these approaches have beenguided by the fact that gray water and black water are often produced bydifferent sources within the same system (e.g., in a residentialplumbing system gray water collected from a shower and black watercollected from a kitchen garbage disposal), and have thus attempted tomeet the needs of such a system by separately plumbing the collectionsystems of the black and gray water sources. This approach isexceedingly expensive to implement, as two separate drainage systemsunder such an approach would need to be installed and maintained.Retrofitting an existing plumbing systems would be even more expensive,if it is possible to do so at all.

Others have anticipated these problems, and have proposed a somewhatmore shared system in which gray and black water are collected. In oneapproach, U.S. Pat. Nos. 5,217,042 and 5,498,330 propose using the samefootprint of an existing plumbing line to plumb a two-in-one drain line.This approach suffers from some of the aforementioned difficulties, inthat extensive retrofitting of the single drain line to a two-in-onedrain line is required. Further, the resulting black and gray waterdrain lines are significantly reduced in their respective diameters,leading possibly to an increased number of blocks, and maintenance timeand expense. In another of these approaches described in U.S. Pat. No.4,112,972, an upstream portion of the drain line is used to collect graywater, and a downstream portion is used to collect black water. Thisapproach is limited to those structures in which black water sources arelocated down stream from gray water sources, an arrangement which is notfeasible for most structures, given the number of different black watersources and their varied locations throughout the structure.

What is therefore needed is an improved gray water system which can beimplemented in most existing structures without extensive retrofitting.

SUMMARY OF THE INVENTION

The present invention provides systems and methods for collecting anddistributing gray water using an existing plumbing structure which canbe implemented in most structures. In a particular embodiment, thesystem includes the existing drain line to which one or more black andgray water sources are connected. The system further includes acollection valve located down stream from at least one of the blackwater sources, the collection valve having (i) an inlet connected to themain drain line, and (ii) an outlet connectable to a black water drainline (e.g., the sewer main or septic tank line) or a gray water drainline. When flow from a gray water source is sensed, the collection valveswitches or remains switched to the gray water drain line where it isfiltered and processed for reuse. When flow from a black water source issensed, the outlet of the collection valve switches, or remains switchedto the black water drain line.

These and other features of the invention will be better understood whenviewed in light of the following drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a gray water reclamation system 100 in accordancewith one embodiment of the present invention.

FIG. 2 illustrates a method for operating the gray water collection anddistribution system shown in FIG. 1.

FIG. 3A illustrates one embodiment of the master controller shown inFIG. 1.

FIG. 3B illustrates one embodiment of the slave controller shown in FIG.1.

FIG. 4A illustrates one embodiment of the flow sensors shown in FIG. 1.

FIG. 4B illustrates one embodiment of the flow sensor comprising atoilet sensor in accordance with the present invention.

FIG. 4C illustrates a method for operating the flow sensor shown in FIG.4A.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

System Overview

FIG. 1 illustrates a gray water reclamation system 100 in accordancewith one embodiment of the present invention. The system 100 includes“black” water sources 120, “gray” water sources 130, flow sensors 140,an existing main interior drain line 150, a collection valve 160, pumphousing 182, a surge tank 184, filtration system 186, an optional graywater collection tank 188, and the gray water appliance 190. The blackwater sources 120 include a toilet 122, a kitchen sink in line with thegarbage disposal 124, and a water softening unit which produces brine126. Gray water sources include a bathroom sink 132, bathtub 134,clothes washer 136, and shower 138.

As illustrated in FIG. 1, both the black and gray water sources drain toa main drain line 150 which connects to a collection valve 160. Thecollection valve 160 directs the drain flow to either a black waterdrain line 172 (e.g., an existing exterior sewer line or drain line toseptic tank), or to a gray water drain line 174. The collected graywater can then be distributed to the gray water appliance(s) 190. In aparticular embodiment of the invention, the gray water appliance 190 isan irrigating system, such as a sub-surface irrigation system. Inanother embodiment, the gray water appliance is a toilet which reusesthe gray water. In still another embodiment, the gray water appliance isa carwash system, or some such other industrial application which canoperate with gray water. Those skilled in the art will appreciate thatthe invention may be used with any appliance which can operate usinggray water.

The system 100 of the present invention further includes flow sensors140 which are configured to detect water flow. As shown, flow sensors141-143 are positioned to detect water flow in the black water drainlines 123, 125 and 127 of the respective black water sources 122, 124and 126. As used herein the term “black water event” refers to thedischarge of water from a black water source. As the flow sensors141-143 are located on black water drain lines 123, 125 and 127, theyare referred to as “black water sensors.” In an alternative embodimentof the invention, flow sensors are located on the gray water drain lines122, 124, 126, and 128 to detect a “gray water event” (i.e., thedischarge of water from a gray water source), and as such will bereferred to as “gray water sensors.” Further alternatively, the system100 may include both black and gray water sensors, i.e., at least onesensor on a black water line and one sensor on a gray water line. Asused herein, the term “flow event” refers to the detection of water flowfrom either a black or gray water source.

The flow sensors 140 further include a collection valve inlet sensor 144configured to sense water flowing along the main drain line 150 into thecollection valve 160, black and gray water drain line sensors 145 and146, respectively, configured to sense water flow in the black and graywater drain lines 172 and 174, respectively. In a specific embodimentshown and described below, the sensors 140 also include a radiotransmitter operable to communicate event signals to the system toinform it of water flow detection. When so configured, the black watersensors are operable to transmit “black water event signals,” the graywater sensors are operable to transmit “gray water event signals,” andthe collection valve sensor 144 is operable to transmit a “water flowevent signal.” Any type of sensor may be selected to detect water flowor a lack of capacity in the storage system, for example, usingmechanical, optical, or electronic sensors, or sensors implementing acombination of these technologies. Further, in addition to detectingwater flow, the sensors 140 may be configured to detect flow rate,volume, temperature and other parameters. The invention is not limitedto the use of any particular sensor technology, and other sensing meansmay be used in alternative embodiments within the present invention. Aspecific embodiment of the flow sensor 140 is shown and described infurther detail below.

Drain line 150 connects to each of the black and gray water sources 120and 130 and terminates downstream at the inlet of the collection valve160. In a particular embodiment, drain line 150 is the existingstructure's drain line which is spliced to add the collection valve 160.In another embodiment, drain line 150 is installed (either upon removalof the previous line, or in the original construction of the structure)to provide a common black and gray water drain line to the collectionvalve inlet. The drain line 150 may be constructed from any materialsuch as iron, copper, brass, PVC, ABS and/or other material which ismost suitable and/or approved by regulation.

The collection valve 160 is operable to connect the main drain line 150to either the black water drain line 172 or the gray water drain line174, referred to herein as the collection valve's “states.” In aparticular embodiment, the collection valve's default and failsafeoperating condition is the black water state in which the valve's outputis connected to the black water drain line 172.

In one embodiment of the invention, a master controller 162 and slavecontroller 164 are used to control the central functions of the system100. Specifically, the master controller 162 is operable to communicatewith the sensors 140, and in response, provide instructions to the slavecontroller 164. Responsive to the instructions, slave controller 164controls the collection valve 160, pump housing 182 and filtrationsystem 186 to operate in the desired state. In a particular embodiment,the master controller 162 is configured to communicate wirelessly tosensors 140, although one or more of the sensors may be hardwiredconnected to the master controller 162 in alternative embodiments. Themaster controller 162 may also include a port for receiving externalcommands such as a shut down command from the user/operator. Adescription of the master controller 162 and slave controller 164 areprovided in FIGS. 3A and 3B, below.

In a particular embodiment, each of the flow sensors 140 operateswirelessly to communicate with the master controller 162. In oneembodiment, the transmitted signals consist of wireless signals such asthose operating within the unlicensed ISM (industrial, scientific andmedical) frequency band, and/or signals defined by conventionally-knownstandards such as “BlueTooth” or IEEE 802.11. Further preferably, eachtransmitted signal is unique in order to determine the correspondingtransmitter's identity. Some or all of aforementioned features may alsobe implemented in a hardwired system in which each sensor is hardwiredto the master controller 162. Other communication means, such as opticalor mechanical, may be used to transmit the sensor signals to thecollection valve 160.

The system 100 further includes a pump housing 182 configured to supplythe collected gray water to the surge tank 184. In one systemembodiment, one or more components of the gray water collection anddistribution system 184, 186 and 190 are located above the main drainline (e.g., when the main drain line is underground and the surge tankor filtration system is located above ground for ease of servicing). Insuch an embodiment, pump housing 182 operates to supply the collectedgray water to the surge tank and/or other above ground systemcomponents. In other embodiments in which the gray water components 184,186 and 190 are located below the main drain line (e.g., where the maindrain line is a drain pipe in the ceiling of a multi-story residence),the collected gray water may be gravity feed to the gray watercomponents 184, 186 and 190, and the pump housing 182 may be omitted.

The surge tank 184 is operable to contain a large volume of water whichmay enter the system from sources such as the bathtub 136 or clotheswasher 138. The surge tank 184 is sized to accommodate the largestexpected volume of water, and may be located above ground to facilitateunit servicing and monitoring. In a specific embodiment, the surge tank184 includes filtering means to remove particulates which wouldotherwise settle in the bottom of the surge tank 184. Furtherspecifically, the surge tank 184 may include components and featuressuch as air vents, overflow port, drain port, cleaning/access port,etc., which are requested or required by regulatory bodies governing theuse of such a system. The apparatus and/or function of surge tank 184may be incorporated into the pump housing 182 or filtration system 186in alternative embodiments. In the embodiment as illustrated, the surgetank 184 includes a sensor 147 configured send a signal to the mastercontroller 162 when the volume or level of the surge tank 186 reaches apredefined point. Water is then either pumped or gravity fed from thesurge tank 182 to the filtration system 186.

The filtration system 186 provides the system's primary gray waterfiltering to reduce the particulates and contaminants in the gray waterto an acceptable level and remove particles which could potentially clogthe gray water appliance 190. The filtration system 186 may also providedis-infection treatment options, such as UV radiation, ozonation,chlorination, enzyme treatment, or other chemical means, to meetsite-specific needs. The degree of filtration and/or dis-infectiontreatment may be adjusted to comply with regulatory requirements, theoperator's wishes, or other considerations. The filtered gray water isthen supplied either by pump or gravity feed to the gray watercollection tank 188 which stores the filtered/disinfected gray wateruntil needed by the gray water appliance 190. The collection tank 188may include a pump or other such apparatus to supply the gray water tothe gray water appliance 190, or the pump may be omitted when the graywater appliance can be gravity-fed, or when the gray water appliance 190itself incorporates a pump. In some embodiments, for example, in aconstantly-fed watering sub-surface irrigation system, the storage tankis not needed as the collected gray water is used as it is produced. Insuch an embodiment, the pump housing 182 and/or the surge tank 184 willhave sufficient capacity to hold the volume of water which is in excessof that taken up by the gray water appliance 190.

The gray water appliance 190 may be any watering apparatus which isapproved for gray water usage. In one embodiment, the gray waterappliance is an irrigation system (above ground or sub-surface) forproviding water to grass, shrubs, plants, vegetation, and/or trees. Inanother embodiment, the gray water appliance 190 comprises a toiletfixture. In still another embodiment, the gray water appliance is a carwashing apparatus. The reader will appreciate that these appliances areonly exemplary and that numerous others may be used in alternativeembodiments under the present invention.

FIG. 2 illustrates a method for operating the gray water collection anddistribution system 100 in accordance with one embodiment of the presentinvention. Initially at 202, the system 100 stands by in a black waterstate, in which the outlet of the collection valve 160 is switched tothe black water drain line 172. Next at 204, water flow into thecollection valve 160 is detected by sensor 144. Next at 206, adetermination is made as to whether a black water event has been sensed.If so, the process returns to 202 where the system continues operatingin the black water state. If not, the process continues at 208, where adetermination is made as to whether a shut off event has been sensed. A“shut off event” may be a system condition which impairs or prevents thesafe collection of gray water, for instance, the overcapacity of graywater presently in the surge or collection tanks 184 or 188, a powerfailure, or a clog which is sensed in a black water source 122, 124, or128. In addition, the operator may also initiate a “shut off event”externally, for instance, by depressing a manual shut off switch.Manually shutting off the system may be desired when the operator isusing one of the gray water sources to handle a black water task, forexample, using a sink to wash diapers, etc.

If a shut off event is not sensed, the process continues at 210, wherethe system is switched to a gray water state. In this state, the mastercontroller 162 provides one or more instructions to the slave controller164 to switch the output of the collection valve to the gray water drainline 174, and to begin operation of the pump and filtration systems 182,184, and 186 in order to process the gray water and supply it to thecollection tank 188. Sensor 146 monitors the flow of the collected graywater and may inform the master controller 162 when flow has stopped,the master controller 162 subsequently instructing the slave controllerto discontinue operation of the pump and filtration systems 182, 184 and186. The process then returns to 202 where the system is switched to ablack water state and the outlet of the collection valve 160 returns tothe black water drain line 172.

FIG. 2 illustrates only one exemplary embodiment of the system in whichwater flow is detected and several others will become apparent to thereader. For example, sensors could be located on one or more of the graywater sources, and the system could change to a gray water statewhenever (i) a gray water event was communicated and (ii) no black waterevents were communicated (assuming that no shut off events occurred).This represents only one of the possible variations which can beimplemented in alternative embodiments under the present invention.

FIG. 3A illustrates one embodiment of the master controller 162 shown inFIG. 1, configured to control a sub-surface irrigation system 190. Inthis embodiment, the master controller controls the operation and/orgathers status from the black water sensors 141-143, the slavecontroller 164, and the gray water appliance 190 comprising anirrigation system.

The master controller 162 includes a wireless radio 305 with RSSI(signal strength) output, a power supply section 310 comprising a 24volts AC power source 311, AC power zero crossing detection 312, andpower supply with backup battery 313, irrigation valve control triacs321 with terminal block 322, valve current detection 323, on-boardmemory 325, slave controller port (if connected with optically isolatedcable versus wireless) 330, a diagnostic port 335 for firmware upgradesand system calibration during installation, user interface whichincludes LCD panel 340 and push button selection switches (not shown),and the micro-controller (uC) 345. This block executes instructions viaflash based firmware to control the interaction between the sensors,slave controller, user selections via user interface,watering/irrigation cycles and the detection of errors within the systemalong with the indication of these errors and/or system status.

The wireless radio 305 is an attachable circuit board with a RFtransceiver, support circuitry for filtering and frequency controllogistics, digital control interface for programming the transceiver bythe uC 345 along with controlling the transmit versus receive sections,phase lock loop status, and received signal strength indication (RSSI)output that will be read by the uC 345 during reception of RF trafficfor determination of validity. The 24 VAC wall power 311 and/or backupbattery 313 are used to supply power to the voltage regulator whichproduces the operating voltage used by a majority of the digitalcircuitry and the wireless radio. The AC voltage is rectified prior tothe regulator to produce raw DC volts. Both voltage sources are diodeconnected for isolation between the power sources and allow reading ofthe individual voltages by the uC 345 for system diagnostics.

AC zero crossing detection 312 is used by the controller to determinewhether the power source 310 is connected and/or supplying power. Thesystem also uses this circuit to determine the frequency of the powersource along with controlling the triacs 321 during the low voltagephase of the cycle for less inductive power reflection and/or surge. Theirrigation valves of the irrigation system 190 (also called stations)are controlled via triacs connected to the uC. The stations areconnected to the controller via the terminal block 322.

During station run time, the valves draw a nominal amount of current.This current is read by the uC 345 via the valve current detectioncircuit 323 and determined to be within specification or not. If drawingexcess current, the station is turned off and the diagnostic systemerror is logged. If no stations are enabled and current flow isdetected, this also causes an error to be logged.

The diagnostic port 335 is used by the installation personnel to getflow calibration data in and out of the system, update the firmware inthe flash based uC 345, enter sensor identity information, and forgeneral data gathering during the installation or calibration phases.

The slave controller communicates with the master controller via theinterface port 330. The interface port 330 may comprise a channel whenthe master and slave controllers are communicating wirelessly, or it maycomprise a electrical or optical connection when electronic or opticalsignal means are used. In a particular embodiment, the master controlleruser interface consists of a LCD panel 340 and pushbutton switches (notshown). This block allows the user to program various features withinthe controller for irrigation, sensor control/status, errorlogging/status, along with any other functions that allow the useraccess to the system.

In a particular embodiment, the uC 345 is connected to a Flash typememory which is designed to be upgraded/updated in the field via thediagnostic port. It also has EEPROM 325 memory to store systemparameters which is non-volatile and is used by the firmware for systemcontrol. It also has an A/D converter section used for valve currentreadings along with determining battery and pre-regulator voltagevalues.

For additional functionality and reliability, the master controller 162sends a signal to each black water sensor 141-143 to check its “health.”In such an embodiment, each sensor responds correctly to the healthcheck, or the master controller 162 provides an instruction to the slavecontroller 164 to operate in a black water state and to issuing an“alarm” to inform the operator of a non-compliant system condition. Forexample, if a sensor battery is low, the system 100 will not collectgray water until the battery is replaced or recharged. This preventsproblems from power failures, low batteries, and sensor or radiomalfunctions. The Controller also controls other elements of the Systemsuch as irrigation valve(s), pump(s), and various warning/flow detectionsensors.

FIG. 3B illustrates one embodiment of the slave controller 164 shown inFIG. 1. The slave controller is operable to controls sensors 144-146,and controls and/or gathers status from the collection valve 160, pumphousing 182, surge/collection tank 184 water level, and filtrationsystem 186.

The slave controller 164 includes an optional wireless radio 355 withRSSI (signal strength) output, a power supply section 360 comprising a24 volts AC power source 361, a power supply 362 with 12 volt pumpbattery 364, a 12 volt battery charger 363, master controller port 365(if connected with optically isolated cable versus wireless), adiagnostic port 367 for firmware upgrades and system calibration duringinstallation, collection valve control/status 367 and 368, pump housingcontrol/status 371 and 372, surge/collection tank water level detection376, irrigation pump control 378 including back flushing of the graywater filter, and the micro-controller (uC) 380.

The optional wireless radio 355 is an attachable circuit board with a RFtransceiver, support circuitry for filtering and frequency controllogistics, digital control interface for programming the transceiver bythe uC 380 along with controlling the transmit versus receive sections,phase lock loop status, and received signal strength indication (RSSI)output that will be read by the uC during reception of RF traffic fordetermination of validity. The 24 VAC wall power 361 and/or battery 364supply the power supply 362 which produces the operating voltage used bya majority of the digital circuitry and the optional wireless radio.

The collection valve 160 is comprised of 3 flow sensor assemblies 144,145, and 146 along with a motor to control the valve. The sensors144-146 communicate with the slave uC 164 through the flow sensorcontrol circuit 382 (located within the slave controller 164 in oneembodiment) and sensor readings are provided back to the uC 380 (afterproper A/D conversion in one embodiment). The collection valve motorcontrol port 367 controls the valve position of the collection valve 160and the uC 380 uses feedback status 368 to ensure that the collectionvalve 160 is in the correct position.

During operation in a gray water state, the collection valve 160 routeswater to the pump housing 182 for initial storage and pump out. Thewater level is determined by a threshold switch for the pump to beturned on by the uC. The period of time that the pump is turned on willbe stored in the slave controller firmware.

The surge/collection tank 184 is supplied water from the pump housing182. The water level is read by the uC 380 from sensor 147 in the tank.The level sensor 147 will be used to determine the amount of water thatis irrigated and provided to the user via the master controller userinterface 365. An irrigation pump is enabled by the slave controller andthe period of time is based on the level of water being reduced to a lowlevel threshold. In one embodiment, this pump is also used to back flushthe gray water filter on a periodic basis (with either gray water, orpotable water provided with an optional valve). City water pressureand/or other pumps may also be used to back flush the gray water filter.

The master controller communicates with the slave controller viainterface ports 330 and 365. The interface ports 330 and 365 maycomprise an RF channel when the master and slave controllers arecommunicating wirelessly, or each may comprise an electrical or opticalconnection when electronic or optical signal means are used.

The diagnostic port 367 is used by the installation personnel to getflow calibration data in and out of the system, update the firmware inthe flash based uC, entering sensor identity information, and generaldata gathering during the installation or calibration phases.

The uC 380 further includes internal Flash type memory (not shown) whichis designed to be upgraded/updated in the field via the diagnostic port367. It also has EEPROM memory to store system parameters which isnon-volatile and is used by the firmware for system control. It also hasan A/D converter section used for water level readings along withdetermining battery and pre-regulator voltage values.

Sensor Architecture and Operation

FIG. 4A illustrates one embodiment of the flow sensors 140 in accordancewith the present invention. The sensor assembly 400 is operable todetect water flow from a monitored water source (either black or gray),and is further configured to communicate the flow event to a controller,which in turn, switches the outlet of the collection valve to theappropriate drain line.

As shown, the sensor assembly 400 includes a transceiver radio 405(“radio” hereinafter), a sensor micro-controller 410, a power supply415, sensor circuitry 420 including: drain/flow sensing element(s) 421and drain/flow control circuit 422, float switch and/or turbine pulsedetector 423, and a PIC micro-controller 424, a diagnostic port 425, andsensor configuration switches 430.

The radio 405 is operable to transmit signals to, and receive signalsfrom, the controller. In a particular embodiment, the radio 405 isoperable to communicate data in one or more channels over the 900 MHzISM (Industrial/Scientific/Medical) band, and in one embodiment may bemodified to additionally operate within the 300-400 MHz range as well.The radio 405 may be adapted to operate in a “frequency agile” manner inwhich the radio 405 and the controller synchronously change theircommunication frequency so as to avoid noise or interfering signalspresent on other channels. The radio may include digital controlinterface for programming the receiver

In a particular embodiment, the radio 405 is an attachable circuit boardwith a RF transceiver, support circuitry for filtering and frequencycontrol logistics, digital control interface for programming thetransceiver by the primary uC along with controlling the transmit versusreceive sections, phase lock loop status, and received signal strengthindication (RSSI) output that will be read by the uC during reception ofRF traffic for determination of validity.

The sensor assembly 400 further includes a sensor micro-controller 410configured to control functions of the sensor assembly 400. In aparticular embodiment, the micro-controller 410 comprises flash-basedfirmware which stores and runs one or more executable programs forcontrolling operations of the assembly 400. Control signals and/or datamay be exchanged between the processor 410 and assembly components viainternal bus lines 412. The micro-controller 410 may include a memorywhich stores the executable programs and/or sensor data obtain from thesensing elements 420. Alternatively, the executable programs and/or datamay be stored in memory (volatile or non-volatile) located outside themicro-controller 410. The micro-controller 410 may be of anyarchitecture (e.g., RISC, etc.), and run on any open, commercial, orproprietary platform (e.g., Linux, Windows, etc.). One embodiment of analgorithm for controlling the sensor circuitry 420 is present below.

The power supply 415 may comprise a battery pack or an external supply,such as AC or DC power. In a specific embodiment in which separatebattery and external supplies are used, they are diode connected forisolation therebetween, allowing for the reading of the individualvoltages by the sensor micro-controller 410 for system diagnostics.

Sensor circuitry 420 includes a float switch or turbine sensor 423 usedto stimulate the wakeup circuit which then brings the micro-controller410 out of sleep mode. Once the micro-controller 410 is awake, thesensor elements require consistent monitoring to determine when theflush cycle has finished. In specific embodiments, the float switch isemployed in a toilet sensor 141 (further described below) and theturbine sensor can be used for battery powered kitchen sensors 142 alongwith some toilet sensors 141 and most soft water back flush sensors 143.

Sensor circuitry 420 further includes one or more sensing elements 421to measure water flow, a process which is described in greater detailbelow. When implemented in the form of a toilet sensor, two separatesensing elements 421 are used in one embodiment to detect flow of bothhot and/or cold water and to determine the ambient temperature of thetoilet water being used during a flush. The ambient temperature willoffset the values being read by the flow/drain element during the flushcycle. In another embodiment, two drain flow sensors may be located in aspaced apart manner to detect drain flow. In embodiments in which thesensors operate in a sleep mode to conserve power, the sensor circuitry420 includes control circuitry 422 to provide normal power to eachsensing element 421 during an active period during which measurementsare taken as described below.

The sensor assembly 400 further include a diagnostic port 425 which canused by installation personnel to get flow calibration data in and outof the system, update the firmware in the micro-controller, enteringsensor identity information, and general data gathering during theinstallation or calibration phases.

Sensor configuration switches 430 are used to program the configurationof the particular sensor consistent with its desired function andoperation. For example, the settings may be used to define a sensor aseither a black or gray water sensor, or define a particular sensor, suchas a toilet sensor as described below. The settings may also be used todefine the sensor's address, how power is to be supplied (battery orexternal), enablement or disablement of particular functions (e.g.,sleep mode, wake-up via float or turbine, etc.)

The sensor assembly 400 may further include additional switches andindicators, such as: a reset switch used during system calibration andinstallation, an error clear switch for the user to tell the system thatan error previously detected has been fixed (plugged toilet will be theprimary use), error LED indicator, system status LED, speaker,microphone, and an A/D converter section used for sensor elementreadings along with determining battery and wall power DC voltagevalues.

FIG. 4B illustrates one embodiment of the sensor assembly 400 comprisinga toilet sensor in accordance with the present invention. The sensorcomponents are generally as described above, albeit with somemodifications as provided below.

The sensor assembly includes two sensor types: drain/flow sensor(s) 421located on the toilet drain line, and toilet input sensors 423comprising a float switch 423 a located in the toilet reservoir and/or aturbine switch 423 b located on the water intake line. The toilet inputsensors 423 are configured to initially detect water flowing into thetoilet reservoir, and generate a wake-up signal in response thereto. Thewake-up signal is subsequently communicated (via wireless or wiredmeans) to the sensor micro-controller 410 located within the sensor 400.The micro-controller 410 upon receiving the wake-up signal, instructsthe power supply to supply power to the toilet drain sensor(s) 421, theoperation of which is described below. In one possible embodiment, thefloat switch 423 consists of a float-actuated switch which detects achange in the water level of the toilet water reservoir. In anotherembodiment, the turbine switch 423 b comprises a mechanical pinwheelassembly such as that described in U.S. Pat. No. 5,721,383 entitled“Flow Meter System and Method of Using Same,” the contents of which areherein incorporated by reference. Other assemblies which use mechanical,electrical, optical or other means to initially sense the flow of watercan be used in alternative embodiment under the present invention.

Once power is supplied to the drain/flow sensor(s) 421, themicro-controller 410 begins monitoring the response of the drain/flowsensor 421 as described below. Once the micro-controller 410 concludesthat drain/flow sensor 421 has detected a black water event, thenmicro-controller 410 controls the radio 405 (located within sensor 400)to communicate (e.g. wirelessly broadcast in one embodiment) a signal tothe master controller 162 that a black water event has been detected.The process by which the radio 405 broadcasts the message to thecontroller is further described below.

Once the black water event message has been transmitted, themicro-controller 410 controls the radio 405 to listen for anacknowledgement signal from the master controller 162 indicating that ithas received the black water event message. If the micro-controller 162determines that the radio 405 has not received the message after apredefined time, the micro-controller 410 will enter into a back offalgorithm in which it waits to retransmit the black water event message.

In one embodiment, the drain/flow sensor(s) comprise two sensors. Afirst sensor 421 a comprises a temperature sensor for monitoring thetemperature of the toilet reservoir water. A second drain/flow sensor421 b comprises a thermistor, or equivalent component or circuit,operable to convert temperature to an electrical voltage/current. Thefirst sensor 421 a is operable to inform the micro-controller of thewater temperature, as this will be a parameter in determining if a flushhas occurred. The second drain/flow sensor 421 b is used to detect waterflow by monitoring the sensor's change in voltage over a predefinedperiod, the change in voltage corresponding to a change in the sensor'stemperature as water flows through the drain line. Specifically, thesecond drain/flow sensor 421 b will exhibit a particular voltage-v-timeresponse corresponding to the temperature change of the sensor resultingfrom water flow within the monitored drain line, that response being afunction of the toilet water temperature which the first sensor 421 ameasures. The process by which the micro-controller interrogates sensors421 a and 421 b to determine if a flush has occurred is described ingreater detail below.

FIG. 4C illustrates a method for operating the sensor assembly 400 inaccordance with the present invention. The method is described in termsof detecting black water flow, although the same process may be usedwith a gray water sensor to detect gray water flow.

Initially at 481, a flow event is detected. The process of detecting aflow event in one embodiment comprises, (i) producing a wake-up signalupon the detection of an initial flow event; (ii) supplying power to thedrain/flow sensor(s) 421 and measuring a response of the flow event; and(iii) correlating the measured response to a stored response, the storedresponse corresponding to a known flow event. In a particular embodimentof process (ii), the micro-controller 410 obtains a measurement of thewater temperature from the first sensor 421 a, and a voltage-v-timemeasurement from the thermistor 421 b. The process of (iii) thencomprises the micro-controller 410 comparing the measured response withone or more baseline voltage-v-time response(s) which has beenpreviously obtained, as will be further described below. The measuredresponse will most closely correlate with one of the baseline responses,and the flow event associated with that closest baseline response willbe determined as the current flow event.

In some embodiments, the measured and baseline responses may notcorrelate closely because of a difference in water temperature betweenthe taking of the baseline and measured responses. In this instance, themicro-controller 410 uses the water temperature information toextrapolate the measured response to the water temperature of thebaseline response, and a more accurate correlation can then be taken. Inan alternative embodiment, the baseline voltage-v-time response can beobtained at various water temperatures and stored. In this instance uponmeasurement, the micro-controller 410 obtains the measured watertemperature, and retrieves that set of baseline responses at thattemperature which most closely approximates the measured temperature.

Next at 482, the flow event message is transmitted to the controller. Asnoted above, gray water sensors will transmit a “gray water event”signal, black water sensors will transmit a “black water event” signal,and sensor 144 at the inlet of the collection valve 160 will transmit a“water flow event” signal. In addition, each sensor's signal will beunique, so that the source of each signal can be ascertained.

Subsequently at 483, the sensor assembly 400 listens for the controllerto transmit and acknowledgement message indicating that it has receivedthe sensor assembly's transmission and has taken the appropriate action.If within a predefined time period an acknowledgement message has notbeen received (484), the sensor assembly 400 initiates a back offalgorithm at 485 which schedules a retransmission of the flow eventmessage after a predefined delay. In a particular embodiment, each ofthe sensors 140 schedules retransmission after different delay periodsso as to minimize the possibility that sensor transmission collide whenattempting to communicate with the controller. If an acknowledgementmessage has been received within the predefined period, the sensorassembly powers down to its sleep mode where it conserves power until asubsequent flow is initially detected.

Sensor Calibration

The present invention uses a system in which black and gray watersources drain along the same line. Accordingly, it is important todetermine when a block in the drain of a black water source may haveoccurred, since these blockages can result in water slowly draining fromthe black water source to emulate a black water event occurring over anextended period of time. In the above embodiment in which the systemswitches collection states upon detection of a black water event,erroneously detecting the black water event will keep the system in ablack water collection state, thereby reducing the system's benefit.

In order to distinguish between normal drainage and when a block mayhave occurred, several voltage-v-time responses can be obtainedcorresponding to normal drainage and varying degrees of blockage. Forexample, upon installation and routine maintenance of the system, thevoltage-v-time responses can be determined for normal drainage, andvarying degrees of blockage, e.g., 25%, 50%, 75% and 100%, the varyingdegrees of blockage being simulated through the use of inserts whichrestrict water drainage to the corresponding percentages. Theseresponses are then stored in the micro-controller 410. As noted above,the responses can be taken at one temperature, or at several differenttemperatures.

Upon the fixture's subsequent use, the sensor's voltage-v-time responseis measured and correlated to each of the stored voltage-v-timeresponses, whereupon the drain's condition is determined by which of thestored responses has the closest correlation to the measured response.Information as to the number of normal drains and blockages occurringover a period of time may be stored in the micro-controller 410 totroubleshoot the system, or to notify that the fixture may be in need ofrepair or replacement.

On normal drains, the measured voltage-v-time response will be closelycorrelated to the stored voltage-v-time normal drain response. Blockageswill be more closely correlated to one of the stored voltage-v-timeresponses of a blocked system. In such an instance, the processor willstore this result, and attempt to alert the system user or maintenancepersonnel that a block has occurred. The master controller 160 will beswitched to the black water state until the block is cleared. In aparticular embodiment, the sensor assembly 400 may include a resetbutton which is depressed when the blockage is cleared (e.g., the toiletor sink block is cleared). Once pressed, the sensor assembly 400 sends asignal to the master controller 162 to resume normal operation, allowingoperation in the gray water state.

In an alternative embodiment in which some amount of constant drainagefrom the monitored source may be tolerated (for instance, a leakykitchen faucet), either the sensor assembly 400 may be configured suchthat this amount of drainage does not trigger detection of a black waterevent, or the master controller 162 may be programmed to continueoperation in the gray water mode if the detected drainage is within apredefined limit.

The foregoing calibration process can also be used to calibrate of graywater sensors having components 405, 410, 415, 420, 425, and 430 asdescribed above. Specifically, in systems 100 configured to switch thecollection state based upon detecting gray water flow, the employed graywater sensors may be configured and calibrated as described above todetect normal drainage, and varying degrees of blockage. Also as notedabove, the gray water sensor assemblies and/or the master controller 162may be configured to permit a predefine amount of drainage withouttriggering a gray water event and switching the state of the collectionvalve 160.

The foregoing description has been presented for purposes ofillustration and description. It is not intended to be exhaustive or tolimit the invention to the precise form disclosed, and obviously manymodifications and variations are possible in light of the aboveteaching. The described embodiments were chosen in order to best explainthe principles of the invention and its practical application to herebyenable others skilled in the art to best utilize the invention invarious embodiments and with various modifications as are suited to theparticular use contemplated. It is intended that the scope of theinvention be defined solely by the claims appended hereto.

1. A gray water collection system, comprising: a main drain line; one ormore black water sources connected to the main drain line; one or moregray water sources connected to the main drain line; and a collectionvalve located down stream from at least one of the one or more blackwater sources, the collection valve having (i) an inlet connected to themain drain line, and (ii) an outlet connectable to a black water drainline or a gray water drain line, further comprising one or more graywater sensors configured to detect water flow from a respective numberof the one or more gray water sources.
 2. A gray water collectionsystem, comprising: a main drain line; one or more black water sourcesconnected to the main drain line; one or more gray water sourcesconnected to the main drain line; and a collection valve located downstream from at least one of the one or more black water sources, thecollection valve having (i) an inlet connected to the main drain line,and (ii) an outlet connectable to a black water drain line or a graywater drain line, further comprising one or more black water sensorsconfigured to detect water flow from a respective number of the one ormore black water sources.
 3. The system of claim 2, wherein the one ormore black water sensors communicate water flow detection to thecollection valve using electrical signals.
 4. The system of claim 3,wherein the one or more black water sensors communicate water flowdetection to the collection valve via a wire.
 5. The system of claim 4,wherein the one or more sensors communicate water flow detection to thecollection valve using a wireless signal.
 6. A gray water collectionsystem, comprising: a main drain line; one or more black water sourcesconnected to the main drain line; one or more gray water sourcesconnected to the main drain line; one or more black water sensorsconfigured to detect water flow from the one or more black water source,each of the one or more black water sensors comprising: a detectoroperable to detect the flow of water from the black water source; and atransmitter for transmitting a black water event signal when black waterflow is detected; and a collection valve having (i) an inlet connectedto the main drain line, (ii) an outlet connectable to a black waterdrain line or a gray water drain line, and (iii) a signal input forreceiving the black water event signal from the one or more black watersensors; wherein, responsive to the reception of the black water eventsignal, the outlet of the collection valve switches to, or remainsconnected to, the black water drain line.
 7. The system of claim 6,wherein the collection valve is located downstream from the one or moreblack water sources.
 8. The system of claim 6, wherein the one or moreblack water sensors communicate the black water event signal via anelectrical signal.
 9. The system of claim 8, wherein the electricalsignal is sent via a wire.
 10. The system of claim 8, wherein theelectrical signal comprises a wireless signal.
 11. The system of claim6, further comprising: a collection valve sensor, comprising: a detectorconfigured to detect water flow at the inlet of the collection valve;and a transmitter operable to transmit a water flow event signal upondetection of water flow into the collection valve, wherein, responsiveto the reception of the water flow event signal, and wherein a blackwater event signal has not been received, the outlet of the collectionvalve switches to, or remains connected to, the gray water drain line.12. The system of claim 6, wherein the collection valve sensorcommunicates the water flow signal via an electrical signal.
 13. Thesystem of claim 12, wherein the electrical signal is sent via a wire.14. The system of claim 12, wherein the electrical signal comprises awireless signal.
 15. The system of claim 6, further comprising one ormore gray water sensors configured to detect water flow from the one ormore gray water sources, each of the one or more gray water sensorscomprising: a detector operable to detect the flow of water from thegray water source; and a transmitter for transmitting a gray water eventsignal when gray water flow is detected, wherein, responsive to thereception of the gray water event signal, and wherein a black waterevent signal has not been received, the outlet of the collection valveswitches to, or remains connected to, the gray water drain line.
 16. Thesystem of claim 15, wherein each of the one or more gray water sensorscommunicates the gray water event signal via an electrical signal. 17.The system of claim 16, wherein the electrical signal is sent via awire.
 18. The system of claim 16, wherein the electrical signalcomprises a wireless signal.